Hydraulic press for electric cables and method of utilizing the same



Dec. 5, 1939. ED, EBY 5- AL 2,182,663

HYDRAULIC PRESS FOR ELECTRIC CABLES AND METHOD OF UTILIZING THE SAMEFiled Feb. 19, 1938 2 Sheets-Sheet l N D t d ne n m E Thomas C.Aitchison,

WW 6.29M 'lheir- Attorney.

Dec. 5, 1939. E. D. EBY ET AL 2,182,663

HYDRAULIC PRESS FOR ELECTRIC CABLES AND METHOD OF UTILIZING THE SAME;-

Inventor-s: Eqgene D. Ebg, Thomas C. Aitchison,

w I Q W Their- Attorney. 7

Patented Dec. 5, 1939 UNITED STATES HYDRAULIC PRESS FOR ELECTRIC CABLESAND METHODOF UTILIZING THE SAME Eugene D. Eby field, Mass,

and Thomas 0. Aitchison, Pittsassignors to General Electric Company, acorporation of New York Application February 19, 1938, Serial No.191,556

' 13 Claims. (01. 140-113) In installations of electric cables, it isnecessary electrically to connect the conductor lengths to form acontinuous circuit. In the majority of cases, this has been done bymeans of connectors which are soldered to the ends of adjacent lengths.There are, however, cases where the application of heat, as in solderingoperations, is highly objectionable on account of the nature of thematerial used to impregnate the conductor insulation. As an alternative,it has been proposed to squeeze or compress the connector as a whole byhydraulic action about the ends of the conductors. Such action naturallyrequires a very large amount of power. Where the cables are laid intrenches, this is a comparatively simple matter because large pressescan be used without special difiiculty but such presses cannot as a rulebe lowered into manholes for use in splicing underground cables. Infact, in most cases, on account of the reduced diameter of the manholeopening, such presses due to their size and weight cannot be used.

Our invention has for its object the provision of an improved hydraulicpress for jointing cables which is sufi'iciently powerful to indent themetal of the connector at spaced intervals into firm electricalengagement with the strands of the conductors and which at the same timeis small enough and light enough to be lowered through the manhole andto be readily handled thereafter in making joints.

For a consideration of what we believe to be novel and our invention,attention is directed to the accompanying description and the claimsappended thereto.

In the accompanying. drawings which is illustrative of our invention,Fig. 1 is a perspective view of our improved press together with thepump for producing the necessary hydraulic pressure; Fig. 2 is an endview, partly in section of the press; Fig. 3 is a cross sectional viewof the press; and Fig. 4 is a longitudinal section of a connector forhollow core fluid filled cable; Fig. 5 is a cross-sectional view takenon line 5 -li of Fig. 4; Figs. 5 to 8 are views illustrating meanswhereby the press may be accurately positioned with respect to theconnector parts; Fig. 9 is a view'illustrating the press and a supporttherefor; and Fig. 10 is a view in elevation showing the press carriedby the support and inclined at an angle thereto.

5 indicates the press which is made of two principal frame parts 6 and1, the parts being united by a cylindrical hinge pin 8. A second andremovable pin 9 or equivalent device is provided to unite the parts whenthey are in position surrounding the connector preparatory to pressingoperation. The pin is slightly tapered to facilitate its removal when itis desired to open the press. ,The cooperating surfaces of the meetingparts of the press frame are nicely fitted and are relatively wide andsubstantial so as to ensure proper alignment when closed about a cableconnector. l0 indicates the barrel or liquid containing member of anhydraulic pump H and I2 is the hand operating lever'thereof. Liquid isdelivered by the pump to the manifold l3 and from it to the pressthrough flexible conduits l4 and IS, the former being connected to thelower half of the press and the latter to the upper half. For somepurposes a single pipe suitably connected to both halves of the presswill be sufficient. A suitable pressure gauge I6 is attached to themanifold so that the operator can see what pressure is being created bythe pump. A valve controlled by the handle I l is employed to releasethe pressure within the manifold press and connected parts when it isdesired to release the rams preparatory to removing the press. While thepump illustrated is well adapted to supply liquid to the press otherforms of pumps may be used, provided they are capable of deliveringliquid at the desired pressure. The press shown is capable of exertingpressures of the order of twenty tons per punch and hence the pump,conduits and other parts should be capable of withstanding suchpressure. The details of the pump form no part of the present invention.

As before stated, the press is made of two principal parts 6 and 1forming the frame and which are united by pins. The press is made in Ithis manner so that it may completely surround the connector whichis tobe attached to the end of a cable conductor, and so that it can readilybe removed "when the work is completed; Each I half of the press framehas two cylinders. l8 and I 9 which open toward the center'axis of thepress and cable. Inside of each cylinder is a ram 20 that is guided inits reciprocating movements by the cylinder wall. It is also providedwith suitable packings 2| which rest in a V-shaped groove in a shoulder22 of the ram. On the opposite side of the shoulder is located a strongcompression spring 23 for retracting the ram when the hydraulic pressureis released. The springs also act to force the liquid employed toactuate the rams from the cylinder spaces, conduits and manifold backinto the. barrel or liquid container ll. Each spring 23 is seated at itsinner end on a flange 24 of a tubular bushing 25 which is screw threadedinto the lower end of a ramcontaining cylinder. Each ram is providedwith a detachable punch 26 having a large flat head which rests squarelyon the inner face of the ram. It is held in place by a screw threadedstud 21 entering the body of the ram. The punches are made detachable sothat others may be quickly substituted when the press is to be used withconnectors of different diameter, or thickness of wall, on both.Similarly, the guide blocks areremovable and for the same reason. Eachpimch has a rounded end, converging sides and sufficient axial length toform a suitable indentation, such as 28, Fig. 4, when the rams areforced inwardly. The shape of the punch facilitates its retraction afterthe pressure is released. Each punch is guided in its movements byguiding sur-' faces 29. The guides for each two punches are formed inthe same block 30, each of the blocks having fiat faces that restsquarely upon and are supported by the frame member adjacent thecylinder ends. The block is held in position by the screw 3| which,however, does not have to carry any appreciable load. The two guideblocks when assembled about theconnector 32 define a cylindrical centralopening the wall or surface of which engages the connector and preventsit from enlarging in diameter when the punches are moved inwardly. Inother words, the guide blocks considered as a unit hold the connector toits initial cylindrical shape. Fig. 2 shows the relation of parts beforethe press acts, and Fig. 3 afterwards. The outer surfaces of each guideblock are in 90 degree relationship and fit into a correspondinglyshaped recess. The adjacent surfaces of the blocks are smooth and flatand located in the horizontal diametral plane of the cable. As a result,not only are the blocks firmly anchored but'they have no opportunity toturn or twist. It will also be seen that the function of the screws 3|is to prevent the blocks from being displaced and not to carry anyappreciable load. In each half of the frame is a port 33 which isconnected to one of the fluid pressure conduits. Extending from the portare passages or channels 34, one leading to each of the cylinders. Thisensures equal pressures on the rams.

When the press is used with cables having hollow cores,with strandssupported on coil springs 351), a strong steel tube 35 is slippedendwise into each of the conductors, the purpose being to prevent thestranded electrical conductor 36 from collapsing when external pressureis applied. Each steel tube has a collar or flange 35a formed integrallytherewith, the purpose of which is to accurately locate the tube withinthe core of the cable, and specifically to prevent the tube from beingpushed too far in the coreof the cable or sipping downwardly into thecore when the end of a cable is elevated or inclined as it ispreparatory to applying a half connector. In Fig. 3, the punches areshown as having moved inwardly and in so doing have made'indentations,such as 28, in the wall of the connector. No attempt has been made inthis figure to show the shape of the individual strands of the conductorbecause the compacting causes them largely to flow together and to moreor less have the appearance of a solid conductor.

It is evident that if pressures of the order of twenty tons per punchare used, as in the present case, without suitable backing the connectorwould be badly distortedas would also the conductors. We avoid this byusing four radially disposed punches spaced 90 apart with guide blocksenclosing and confining the connector except in line with the punchesand operating the punches simultaneously, thus imparting to eachsubstantially the same force. Due to this arrangement, the pressure dueto one punch is balanced by that of the punch diametrically opposite it.From this, it follows that since the punches move radially inward andsince the forces exerted are balanced no stresses are imparted to thecables tending to injure them when the press is in -use. When the guideblocks are assembled, as best shown in Fig. 3, they form a square andthe outward pressures thereon due to the action of the punches on theconnector are taken by the solidly built frame members 6 and I. The pins8 and 9 are sufficiently strong to prevent any separation of the frameparts when the punches are in action. After the fluid pressure isremoved and the rams are retracted by the compression springs, the pressas a whole may be adjusted longitudinally of the connector preparatoryto further punch operations. With the pressure removed, it is a simplematter to drive out the tapered pin 9 and open the press.

In Fig. 4 is shown'a connector comprising two similar parts 31 and 38,each having a passage 39 communicating with the channels in the cores ofthe conductors. Each half connector has a slightly tapered.valve seat 40for the reception of a plug valve 4i whereby the outward flow of liquidfrom the cable may be controlled as well as the flow from cable tocable. Extending outwardly from the seat and valve is a port 42 wherebya controlled amount of liquid from the cable may be discharged to removeforeign matter.

Each half connector has an internally formed socket to receive an end ofa stranded conductor 36, and a hollow cylindrical part which is ofrelatively thick metal in which are preformed longitudinally extendingshallow grooves 44* spaced apart. The halves of the connector areenclosed in a sleeve 43, Fig. 4, having relatively thin walls, portionsof which are subsequently forced inwardly into the grooves to formindentations 44. When so forced, the metal of the sleeve 43.

firmly unites the halves of'the connector and thus a through confiningpassage'forthe impregnating liquid of the cable is established.

It is important that the pressures applied by the press shall notdistort the metal'of the connector in the region of the valve seat"because such distortion would result in the failure of the valve toseat properly. This means that the location of the indentations withrespect to the valve seat becomes an important factorin securing thebest results. For this purpose, a pair of pins or equivalent devices 45,5 are mounted on opposite sides of the upper half of the guide block 30.On the connector is detachably mounted a locating block 46. The side ofthe locating block presented to the press is provided with a notch 41with which a pin 45 on the guide block 39 is adapted to engage. In orderthat the locating block may be accurately positioned, it is provided onits under side with a small pin 48 which fits into the port 42. As shownin Figs. 5 and 6,

the locating block 46 has its notch 41 facing the left with its pin 48in the fluid escape port 42 and a pin 45 on the guldeblock entering it.By this simple arrangement of parts, the press may be accuratelypositioned in an axial direction, and because of the location of the pin45 inthe notch, it is angularly positioned as well.

Because one end of each connector is made of relatively .thick metal andhas preformed grooves designed to receive the metal of the sleeve 43, itfollows that the press must be so angularly positioned around theconnector that the punches 5 will be in radial alignment with thegrooves. This is done by reversing the position of the locating block asshown in Figs. 7 and 8 with the result that the depressions orindentations in the sleeve caused by the punches will register with the1 grooves 44*- and fit tightly therein.

In Fig. 9 an arrangement of parts is shown such that, for the sake ofsimplicity, one pipe from the pump may be used instead of two as shownin Fig. 1. The fitting 58 receives a flexi- 15 ble pipe 59 leading fromthe pump and a second flexible pipe 60 leading to a fitting 6| on theupper half of the press, the two pipes being in series. The pipe 60 ispurposely made relatively long with a generous bend to avoid damage and0 to permit the press to be opened and closed after the tapered pin 9 isdriven out.

Desirably in applying the half connectors, the ends of the cable areupturned to form traps to prevent the admission of air and other foreigng matter. Under these conditions, it is desirable to support the pressby suitable means so as not to stress the cable. In Fig. 9 is shown asupport suitable for the purpose. It comprises a fiat base member 50having a pair of upturned ears located on opposite sides thereof. Abovethe base is a member 52 having downwardly extending ears 53. The earsare united on the one side by a pivot pin 54 and on the other side by apin 55 having its outer end screw threaded to receive a wing nut 56. Theupper member 52 is firmly attached to the press, as for example, by studbolts 51 which are seated in the lower half of the press 6. In Fig. 10,the press is shown supported at the proper angle to receive the up- 40wardly inclined end of a cable preparatory to applying a half connector.When the press is used to secure the uniting sleeve 43 over the adjacentends of the half connectors, the press will stand vertically with thebase member 50 at right 45 angles thereto.

Assuming that a half connector is to be applied to a cable end which isinclined upwardly the press is placed on a suitable support, such as isshown in Figs. 9 and 10, with the axis of the Y 50 press coinciding withthe axis of the upturned cable end. A small piece of the spiral spring35 Fig. 4 is pulled out and out 01f, then the steel tube 35 is pushedinto the core of the cable until the collar on the end is in firmcontact with the 5 ends of the stTands: The connector half is thenslipped over the end of the conductor and both are located inapproximate positions in the lower half of the press. Next, the exactposition of the connector in the punch guide block is secured by 0 thelocating block. Sufficient pressure is then applied to the punches tohold the connector in its position. The end of the conductor is thenforced into place to fully seat it after which the final pressure isapplied to the punches by means 05 of the rams. When this operation iscompleted,

thepressure on the rams is released by opening the valve II at the pumpand the springs 23 will withdraw the punches. Care should be taken tosee that the working ends of the punches are 7 cleaned and well oiled.The end of the other cable to be jointed is similarly treated.

After the cable ends have each been provided with a half connector, thecables are trained into final alignment. The sleeve 43 is then slipped75 into place over the tubular end of one of the connectors. Theconnector and sleeve are next located in their approximate positions inthe lower half of the press and later moved to exact longitudinal andangular positions, using for the purpose the locating block. The punchesare then 5 caused to be moved inwardly by a suflicient" amount to holdthe parts in position and later the final pressure is applied to makethe indentations and then released. After the second half connector. isseated in the sleeve 43, the press is 10 opened and moved over thatportion of the sleeve enclosing the second connector half, next thepress is closed and the above described operations repeated.

In rare cases, it becomes necessary to remove 5 a connector. It isimportant that this be done without injuring the cables since in somecases there may not be enough slack in a manhole to permit of cuttingoff any part thereof. One of the advantageous featuresof thelongitudinal indenta'tions located 90 degrees apart is that theconnector can be removed and a new one substituted. This can be done bysawing through the connector in a plane at right angles to the axis ofthe cable and in a plane registering with 2 the end of the conductorstrands. This leaves a part of the connector in the form of a ferruleattached to the strands by four indentations. Between the indentations,the ferrule is not deformed as indicated in Fig. 3 and at these pointscan be sawed through in a plane in the axis of the cable. By makingeither two opposite saw cuts through the ferrule down to the strands, orfour if desired, the ferrule may be split ofi or removed from thestrands without damaging them. This leaves the strands in the form theyassumed after the original connector was pressed into place. By bindingthe ends of the strands With,a temporary clamp, a new half connector canbe fitted over the strands and pushed on to the same position as theoriginal connector. The press can then be applied and the indentationsmade in the new connector opposite the depressions in the strands sothat the I new connector occupies the same position as the original.From the foregoing, the importance of longitudinally extendingdepressions or indentations as distinguished from circumferentialgrooves becomes apparent for in the latter case the connecto cannotreadily be axially split and removed. The indentations are desirablyrelatively long compared to their width and are sufliciently dee tocompact the strands in close contact with each other and the connectorpart, thereby firmly uniting the parts and establishing 5 goodelectrical connection with the strands.

The division of'the press frame into parts is desirable in all cases tofacilitate the use of the press, and is necessary when a sleeve 43 isemployed to unite the half connectors since otherwise the press couldnot be removed as it completely surrounds the cable connector.

The press has been described in connection with a cable joint but it canwith advantage be used for connecting other conductors and specificallyfor connecting a cable end to a terminal stud. 1

Since the heads of the cylinders are integral with the frame members,all danger of leakage in these regions is avoided. Should the pack- 7ing of a ram become worn, it .can be replaced by first removing theadjacent guide block and then the tubular bushing 25. After this isdone, the ram and its punch can be removed giving full access to thepacking.

Notwithstanding the very great pressures which can be exerted on thepunches, in this case twenty tons, the complete press has a weight ofthe order of eighty pounds, and therefore presents no difficulty inhandling even in the crowded space of an underground cable manhole.

The construction of the connector illustrated in Fig. 4 is not claimedherein, it being the sole invention of Eugene D. Eby.

What we claim as new and desire to obtain by Letters Patent of theUnited States is:

1. A press comprising separable frame members arranged to encircle apiece of work, means l pressure simultaneously for converting themembers when they encircle the work, cylinders formed in each of themembers, each cylinder in one member being in the same diametral planeas a cylinder in another member, a ram for each cylinder, a punch foreach ram, for indenting the work, afixed guide block having radicalopenings for the punches and. also a central work receiving opening, the

wall of which limits the radial distortion of the work extendingtherethrough as the punches move inwardly, and means admitting fluidunder to all of the cylinders to cause the rams to force the punchesinto the work and form indentations therein.

2. A press comprising a pair of frame members,

means for uniting the members in a manner to define a work receivingopening, a pair of radially disposed cylinders formed in each of themembers, a ram in each cylinder, a retractile means for each ram, apunch movable with each of the rams, a flxedguide having openings withradial walls for guiding the punches and a central opena hinge formindentations, and

ing through which the work extends, the wall of the central openingpreserving the initial contour of the work when the punches enter it andmeans for supplying fluid under pressure to all of the cylinders forsimultaneously moving the punches radially inward through the guideopenings into engagement with the work to form indentations therein.

3. A press comprising a pair of frame members, connection between two ofthe adjacent ends of the frame, a locking connection between the othertwo ends, a pair of radially disposed cylinders formed in each ofthe'members, a ram in each cylinder arranged to move in a radial planewith respect to the work, a retractile means for each ram, a punchattached to and movable with each ram, a guide block divided in adiametrical plane passing through the hinge connection which enclosesthe work and confines it against enlargement, the block having radialopenings through which the punches extend to indent the work, and meansfor supplying fluid under pressure to all of the cylinders forsimultaneously moving the punches radially inward through the openingsinto engagement with the work.

4, A press comprising a pair of detachably connected frame membersdefining a substantially square central opening, radially disposedcylinders in the members, a ram in each of the cylinders, a punchattached to each ram having definitely converging sides and a roundedend, a divided guide block, the outer walls of which fit the squarecentral opening, having radial openings through which the punches extendand are guided by the walls thereof for engagement -with the work, andmeans for supplying fluid pressure to all of the rams to causesimultaneous inward movement of the punches.

5. A press for cable connectors of tubular form in which the ends ofstranded conductors are located, comprising detachably connected framemembers, a pair of radially disposed cylin ders in each of the members,a ram in each cylinder, means for simultaneously admitting fluid underpressure to the cylinders for moving in its corresponding cylinder, arelatively narrow punch moved inwardly by each of the rams to form arelatively long narrow indentation in the peripheral wall of theconnector, and a diyided guide block for the punches, the parts of theblock being secured one to each half of the frame members and separabletherewith, the block having radial openings for guiding the punches intothe work, and a-central opening, the wall of which preserves thefinitialcontour of the work as the punches tend to distort it.

6. A press for cable connectors of tubular form in which the ends ofstranded conductors are located, comprising detachably connected framemembers, a pair of radially disposed cylinders in each of the members, aram in each cylinder, means for simultaneously admitting fluid underpressure to the cylinders for moving the rams radially inward, aretractile spring in each cylinder for moving the rams outwardly awayfrom the connector when the fluid pressure is released, an abutment foreach spring located in its corresponding cylinder, a, relatively narrowpunch moved inwardly by each of the rams to form a relatively longnarrow indentation in the peripheral wall of the connector, and a pairof guide blocks supported by the frame members, each block having guidesurfaces for a pair of punches and outer surfaces extending at right.angles to each other engaging the members and fiat meeting faces, theblocks defining a central opening, thewalls of which enclose theconnector and prevent distortion thereof when the punches move inwardlyto make indentations in the peripheral surface of the connector.

'7. A press comprising frame members arranged to encircle a hollow pieceof work connector, means permitting the members to be opened to encirclethe work and thereafter be closed around it, a pair of radially disposedcylinders formed in each of the members, each cylinder in one memberbeing diametrically aligned with a cylinder in another member, a ram foreach cylinder, a punch actuated by each ram, a guide block having radialguiding surfaces for the punches and a central opening to receive thework, the wall of which limits the radial distortion of the work, a tubeinside of the work for preventing the collapse thereof when the punchesare forced inwardly, and means for admitting fluid under high pressuresimultaneously to all of the cylinders to cause the rams to force thepunches into the outer wall of the work to form radial y displacedindentations therein.

8. A press comprising opposed separable frame members which whenassembled define between them an opening having a non-circular wall, a hnge pin uniting the members on one side, a releasable means for unitingthe members on the opposite side, cylinders formed in each of themembers, each cylinder in one member being in the same diametral planeas a cylinder in another member, a ram for each cylinder, a punch foreach ram, a hollow guide block for the punches, the outer wall of whichengages the non-circular wall of the members and is held in fixedposition thereby, the guide block having radial openings for the punchesand a central work receiving opening, the wall thereof confining thework extending therethrough, and means admitting fluid pressuresimultaneously to all of the cylinders to cause the rams and punches tomove radially inward and form indentations in the work.

9. A portable press for indenting hollow articles, comprising detachablyconnected frame members encircling the work, diametrically opposedcylinders in the members, rams in the cylinders, punches actuated by therams, radially disposed guide means for the punches, means for supplyingfluid to all of the cylinders in a manner to cause simultaneousoperation of the rams and punches, and means for definitely positioningthe press in axial position on the article preparatory to operating itcomprising a device attached to the press and a cooperating devicesupported by the article.

10. A press for indenting hollow articles, comprising detachablyconnected frame members, diametrically opposed cylinders in the members,rams in the cylinders, punches actuated by the rams, radially disposedguide means for the punches, means for supplying fluid to all of thecylinders in a manner to cause simultaneous operation of the rams andpunches, and means for locating the press preparatory to operating itcomprising a pin carried by the press and a block carried by thearticle, the b ock having a notch in one of its faces to receive thepress pin, and a pin on the under side of the block which fits into thearticle.

11. A press comprising frame members arranged to encircle a piece ofwork, means permitting the members to be opened to encircle the work andthereafter be closed around it,

cylinders formed in each of the members, each receiving opening,

, by the connector.

cylinder in one member being in the same diametral plane as a cylinderin another member, a ram for each cylinder, a punch for each ram, aguide block for the punches having a work the wall of which limits theradial distortion of the work extending therethrough, means admittingfluid under pressure simultaneously to all of the cylinders to cause therams to force the punches into the work and form indentations therein, asupport for the press having a flat base, an element secured to one ofthe frame members, and adjustable connecting means between the base andthe element.

12. The method of applying a connector to a hollow core stranded cablewhich comprises inserting a metal tubeinside of the core defined by thestrands to prevent collapsing of the core when subjected to externalpressure, inserting an end of the cable into a hollow metal connector,and simultaneously forcing a plurality of punches radially inward fromopposite sides of the axis of the connector to form shallow axiallyextending indentations therein to unite the strands of the conductor andthe metal of the connector.

13. A portable hydraulic press for indenting hollow cable connectorscomprising hinged frame members, diametrically opposed radially disposedcylinders in the members, a ram in each cylinder, radially movablepunches operated by the rams, a guide block through which the punchespass prior to indenting the connector, means for simultaneouslysupplying fluid under pressure to all of the cylinders to actuate therams, and means for definitely positioning the press about the connectorboth axially and angularly preparatory to the pressing operation, onepart of the means being on the press and movable therewith and anotherpart definitely fixed as to its position EUGENE D. EBY. THOMAS C.AITCHISON.

CERTIFICATE OF CORRECTION. V Patent No. 2,182,665., December 5, 19 9.

EUGENE D. EBY, ET AL.

It is hereby certified that error appears in the printed specificationof the abovenumbered patent requiring correction as follows: Page Lfirst column, line 11;, claim 1, for the word "converting" readconnecting; line 20, for "radical" read radial; and that the saidLetters Patent should be read with this correction thereinthat the samenay conform to the record of the case in the Patent Office.

Signed and sealed this 50th day of January, A. D. 19LLo.

Henry Van Arsdale,

( Acting Commissioner of Patents.

